(1) Field of the Invention
The present invention relates generally to torque transmitting joints and, specifically, to double Cardan joints.
(2) Description of Related Art Including Information Disclosed under 37 CFR 1.97 and 37 CFR 1.98
Torque transmitting joints are used in a wide variety of applications and especially in vehicle applications. Such joints generally transmit torque from an input shaft to an output shaft. Universal (“U”) joints or Cardan joints are in widespread use in heavy machinery applications and in automobiles and trucks and they accommodate changes, in service, in the angle between the input shaft and the output shaft, referred to hereinafter as the operating angle. Double Cardan joints include two universal joints so arranged that each accommodates one half of the operating angle. Double Cardan joints split the operating angle into two separate angles that are half of the operating angle. Double Cardan joints come closer to achieving constant velocity torque transmission than do single Cardan universal joints. However, in heavy duty applications, for example, double Cardan joints can become quite bulky and heavy. Such joints, with heavy parts rotating at high speeds at substantial distances from the axes of the shafts, have high inertia and are susceptible to undesired and excessive vibration.